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Abstract
Rabies is a major neglected zoonotic disease, despite the availability of highly sensitive diagnostic tests and efficacious human and animal vaccines. Perpetuation of rabies among multiple species of bats and wild carnivores, together with the presence of diverse lyssaviruses, remains a challenge for the prevention and control of this disease. However, most of the global burden may be reduced by mass vaccination of dogs, the major reservoir. Elimination of human rabies mediated by dogs may be feasible, based upon the elicitation of herd immunity, the application of sound health economic principles for appropriate disease management and technology transfer to those developing countries where rabies is hyper-endemic. Global canine rabies elimination has clear benefits for public health, veterinary medicine and conservation biology, so these sectors must collaborate using a transdisciplinary 'One Health' approach that allows the creation of long-term regional strategies for enhanced surveillance and practical intervention.
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New steps in the control of canine rabies in India. DEVELOPMENTS IN BIOLOGICALS 2008; 131:157-166. [PMID: 18634476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In India, about 20,000 people die of rabies every year. The dog is the main reservoir and transmitter of the disease. A pilot rabies control programme was launched in five Indian federal states in February, 2007. This initiative is led by the Animal Welfare Board of India (AWBI) federating many animal welfare organizations and the Ministry of Agriculture. It aims at creating a "Rabies Free India." The programme combines parenteral vaccination of accessible owned and stray dogs, spaying/neutering followed by parenteral vaccination and oral vaccination of inaccessible dogs. The freeze-dried vaccine SAG2, including the bait casing, was registered in India following successful evaluation of vaccine-bait safety and efficacy (by survival after virulent challenge) in captive Indian stray dogs in the Bhopal High Security Animal Disease Laboratory. Furthermore, bait acceptance was tested under both experimental and field conditions.
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Can rabies be eradicated? DEVELOPMENTS IN BIOLOGICALS 2008; 131:95-121. [PMID: 18634470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Rabies, an acute progressive encephalitis, is an ancient zoonosis. Its distribution encompasses all continents, except Antarctica. Agents consist of at least 11 species orgenotypes of rhabdoviruses, in the Genus Lyssavirus. Susceptible natural hosts include all mammals. Primary reservoirs reside in the Orders Carnivora and Chiroptera. A plethora of variants, maintained by a diversity of abundant hosts, presents a challenge to a strict concept of true eradication. Globally, the domestic dog remains the most significant species for viral transmission, responsible for millions of suspect human exposures and tens of thousands of fatalities. As such, this single major target provides an ideal opportunity for focused intervention programmes in humane disease prevention and control, driven by laboratory-based surveillance and guided via modern epidemiological insights. Historically, substantial technical progress throughout the 20th century led to the development of safe, affordable and efficacious animal and human vaccines, resulting in declining disease burdens in selected developed and developing countries. Regional and local disease resurgence occurs, due in part to a combination of political and economic instability, environmental perturbations, and shifting government priorities. Society must recall that despite the recent recognition of other important emerging infectious diseases, none exceed the case fatality rate of rabies. Given the clear relevance of rabies in public health, agriculture, and conservation biology, substantive international progress must continue towards enhanced public awareness, human rabies prevention, wildlife rabies control, and canine rabies elimination, with renewed collaborative vigour.
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The safety and efficacy of the oral rabies vaccine SAG2 in Indian stray dogs. Vaccine 2007; 25:3409-18. [PMID: 17224221 DOI: 10.1016/j.vaccine.2006.12.054] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 12/12/2006] [Accepted: 12/21/2006] [Indexed: 11/22/2022]
Abstract
India is one of the countries with the highest prevalence of human rabies throughout the world. Dogs are primarily responsible for rabies transmission. Among them, stray dogs play a major role in that country. Parenteral vaccination programmes are insufficient to eliminate rabies partly due to difficulties in establishing satisfactory immunisation coverage in the dog population in view of the high proportion of stray dogs. Oral vaccination may be a useful adjunct to parenteral vaccination by increasing dog vaccination coverage. Safety, immunogenicity and efficacy of Rabidog SAG2 bait were evaluated in Indian stray dogs in captivity. Safety of SAG2 was demonstrated by the absence of adverse clinical sign, salivary excretion and absence of replication of the vaccine strain in brain and salivary glands of 21 vaccinated dogs, even when immunodepressed. Efficacy was shown 109 days post-vaccination after challenge with a highly virulent street rabies virus which killed all five controls whereas all nine vaccinated dogs survived, despite the fact that only five out of nine had seroconverted before challenge.
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Assessing the burden of human rabies in India: results of a national multi-center epidemiological survey. Int J Infect Dis 2007; 11:29-35. [PMID: 16678463 DOI: 10.1016/j.ijid.2005.10.007] [Citation(s) in RCA: 231] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Revised: 09/19/2005] [Accepted: 10/06/2005] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE Human rabies has been endemic in India since time immemorial, and the true incidence of the disease and nationwide epidemiological factors have never been studied. The main objectives of the present study were to estimate the annual incidence of human rabies in India based on a community survey and to describe its salient epidemiological features. METHODS The Association for Prevention and Control of Rabies in India (APCRI) conducted a national multi-center survey with the help of 21 medical schools during the period February-August 2003. This community-based survey covered a representative population of 10.8 million in mainland India. Hospital-based data were also obtained from the 22 infectious diseases hospitals. A separate survey of the islands of Andaman, Nicobar, and Lakshadweep, reported to be free from rabies, was also undertaken. RESULTS The annual incidence of human rabies was estimated to be 17,137 (95% CI 14,109-20,165). Based on expert group advice, an additional 20% was added to this to include paralytic/atypical forms of rabies, providing an estimate of 20,565 or about 2 per 100000 population. The majority of the victims were male, adult, from rural areas, and unvaccinated. The main animals responsible for bites were dogs (96.2%), most of which were stray. The most common bite sites were the extremities. The disease incubation period ranged from two weeks to six months. Hydrophobia was the predominant clinical feature. Many of the victims had resorted to indigenous forms of treatment following animal bite, and only about half of them had sought hospital attention. Approximately 10% of these patients had taken a partial course of either Semple or a cell culture vaccine. The islands of Andaman, Nicobar, and Lakshadweep were found to be free of rabies. CONCLUSION Human rabies continues to be endemic in India except for the islands of Andaman, Nicobar, and Lakshadweep. Dogs continue to be the principal reservoir. The disease is taking its toll on adult men and children, the majority from rural areas, due to lack of awareness about proper post-exposure immunization. The keys to success in the further reduction of rabies in India lies in improved coverage with modern rabies vaccines, canine rabies control, and intensifying public education about the disease.
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Impact of zoonoses on human health. VETERINARIA ITALIANA 2006; 42:369-379. [PMID: 20429071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
By reviewing the most significant zoonotic disease outbreaks that have occurred mostly during the past ten years, the author provides a clear idea of how varied these diseases can be in regard to their aetiological agent, size and direct impact on public health. Most examples involve emerging zoonotic diseases caused by viruses and prions and transmitted to humans by a bite, close contact with affected live animals or carcasses, or through the consumption of their tissues. These outbreaks vary from very small and localised clusters of individual cases to millions of deaths, as reported during the past influenza pandemics. The author also shows that even for the larger outbreaks, the direct impact on public health measured by the morbidity and mortality of zoonoses is largely inferior to that of major communicable diseases that affect only humans, particularly human tuberculosis, malaria, HIV/AIDS. However, it is very difficult to predict the outcome on public health of these emerging zoonotic diseases since transmission patterns are not always sufficiently understood to assess this impact accurately. In addition, new modes of agent transmission may compound the initial impact on public health. Finally, the author indicates additional reasons that explain why these diseases are important by placing special emphasis on the financial losses recorded in both human and animal health and also the societal non-monetary losses these diseases can incur. Lessons learnt following major crises generated by the emergence of zoonotic diseases, such as bovine spongiform encephalopathy, severe acute respiratory syndrome and avian influenza, are provided.
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Human rabies prevention. DEVELOPMENTS IN BIOLOGICALS 2006; 125:155-64. [PMID: 16878473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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[Xenografts and public health: international political perspectives]. PATHOLOGIE-BIOLOGIE 2000; 48:450-2. [PMID: 10868423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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[Brief review of the history of zoonoses]. REV SCI TECH OIE 2000; 19:15-22. [PMID: 11189711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
By studying the surviving documents describing surveillance and methods of control of zoonoses in the distant past, the history of the fight against these diseases can be retraced. Prior to the 20th Century, the best known zoonoses were, amongst others, rabies, anthrax, glanders, tuberculosis, plague, yellow fever, influenza, and certain zoonotic parasitic diseases. An analysis of historical events yields a number of lessons as to the positive and negative influences of past theories regarding the aetiology, contagiousness and control of these diseases. These lessons serve as a reminder, to all those involved in the fight against emerging zoonoses, of the urgent need for extensive research on the aetiology and mode of transmission of these zoonoses, in addition to the need for timely application of the findings of such research to disease control activities.
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Abstract
Many new, emerging and re-emerging diseases of humans are caused by pathogens which originate from animals or products of animal origin. A wide variety of animal species, both domestic and wild, act as reservoirs for these pathogens, which may be viruses, bacteria or parasites. Given the extensive distribution of the animal species affected, the effective surveillance, prevention and control of zoonotic diseases pose a significant challenge. The authors describe the direct and indirect implications for public health of emerging zoonoses. Direct implications are defined as the consequences for human health in terms of morbidity and mortality. Indirect implications are defined as the effect of the influence of emerging zoonotic disease on two groups of people, namely: health professionals and the general public. Professional assessment of the importance of these diseases influences public health practices and structures, the identification of themes for research and allocation of resources at both national and international levels. The perception of the general public regarding the risks involved considerably influences policy-making in the health field. Extensive outbreaks of zoonotic disease are not uncommon, especially as the disease is often not recognised as zoonotic at the outset and may spread undetected for some time. However, in many instances, the direct impact on health of these new, emerging or re-emerging zoonoses has been small compared to that of other infectious diseases affecting humans. To illustrate the tremendous indirect impact of emerging zoonotic diseases on public health policy and structures and on public perception of health risks, the authors provide a number of examples, including that of the Ebola virus, avian influenza, monkeypox and bovine spongiform encephalopathy. Recent epidemics of these diseases have served as a reminder of the existence of infectious diseases and of the capacity of these diseases to occur unexpectedly in new locations and animal species. The need for greater international co-operation, better local, regional and global networks for communicable disease surveillance and pandemic planning is also illustrated by these examples. These diseases have contributed to the definition of new paradigms, especially relating to food safety policies and more generally to the protection of public health. Finally, the examples described emphasise the importance of intersectorial collaboration for disease containment, and of independence of sectorial interests and transparency when managing certain health risks.
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Abstract
The national health authorities of Sri Lanka have adopted a combined strategy of rabies vaccination and stray dog removal to control endemic dog rabies. Despite the control efforts, an increase of animal and human rabies cases has occurred since 1994. As a consequence, a project to evaluate the national rabies control program has been started and a study focussing on the dog population and rabies control activities in a limited area of Mirigama was conducted. Information on canine abundance and the accessibility of dogs for rabies vaccination was obtained by a household survey, vaccination of dogs against rabies at several vaccination points, collar-marking, and transect line recapture. The number of unvaccinated dogs was estimated by using Bayesian methodology. The estimated number of dogs per square kilometre was 87 (95% credibility interval: 80, 93) for owned dogs and 108 (100, 116) for owned and ownerless dogs. Coverage after the immunisation campaign was 57.6% (53.3, 61.9%) if vaccination at the vaccination points was considered and 66% (60.4, 72.0%) if recently provided vaccination by private veterinarians was also taken into account. The proportion of households with at least one dog vaccinated varied between 59.1 and 94.2% within the catchment area of the different vaccination points. Unvaccinated dogs were puppies (12%), ownerless dogs (57%), and owned dogs, which were not presented for vaccination (31%). In order to improve the rabies immunisation coverage among dogs and to achieve complete elimination of rabies it was recommended that the 95% catchment area of each vaccination point be assessed, the distribution of vaccination points in the vaccination area be redefined if necessary, a system for the vaccination of dogs missing the vaccination campaign for dog owner-specific reasons be established, and an inexpensive marking system be used for vaccinated dogs.
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Monitoring infectious diseases. Ann N Y Acad Sci 1998; 862:205-10. [PMID: 9928226 DOI: 10.1111/j.1749-6632.1998.tb09137.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Field evaluation of a dog owner, participation-based, bait delivery system for the oral immunization of dogs against rabies in Tunisia. Am J Trop Med Hyg 1998; 58:835-45. [PMID: 9660475 DOI: 10.4269/ajtmh.1998.58.835] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We evaluated a dog owner, participation-based, bait delivery system for the oral immunization of dogs against rabies. In a field study in a semirural area of northern Tunisia, dog owners were asked to come to temporary bait delivery sites. A total of 314 baits were given to 178 dog owners in four sites. The experimental baits used consisted of a freeze-dried core unit containing sulfadimethoxine (SDM) as a biological marker and an aromatized paraffin envelope. No vaccine was used. Preliminary tests had shown that by using a rapid commercial card test, positive SDM serum levels were detected in more than 95% of dogs up to two days after bait ingestion. During the two days following bait delivery, we visited more than 95% of all households in the study area and took blood samples from as many owned dogs as possible. Unconsumed baits were recovered and human contacts with the bait matrix were recorded. The campaign required 7.6 person-min per bait and 13.5 person-min per dog owner for providing baits, gloves, and instructions. The estimated average cost effectiveness ratio per dog accepting a bait was 1.7 US dollars. From the indications given by the dog owners and the results of the SDM test, it was concluded that 85-90% of the owned dogs in the study area had consumed a bait at least partially. Of 314 baits delivered, 78.7% were fully consumed by dogs and 4.1% were recovered during the household survey. The remaining baits (17.2%) that were not recovered were either not consumed or only partially consumed by the target dogs (3.7 baits per 100 inhabitants). These baits probably remained within the highly populated areas and were potentially accessible to other domestic animals and other nontarget species, including humans. Twenty-five unprotected human contacts with baits were recorded (1.7% of all inhabitants). Our study has demonstrated the potential of dog owner based bait delivery. This technique is simple and efficient, particularly if the human population is accustomed to mass immunization in defined centers. Before applying this method on a large scale with live vaccine loaded baits, further studies should focus on minimizing the number of human contacts with the vaccine bait, systematizing contact identification and establishing structures in ensuring proper treatment if exposure to vaccine should occur.
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Field evaluation of two bait delivery systems for the oral immunization of dogs against rabies in Tunisia. Vaccine 1998; 16:657-65. [PMID: 9562683 DOI: 10.1016/s0264-410x(97)00259-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Two bait delivery systems for the oral immunization of dogs against rabies were tested in small scale field trials in a semi-rural area in Tunisia: bait delivery to owned dogs during door to door visits of households (door to door baiting) and distribution of baits on transect lines (transect line baiting). A prototype bait (DBL2) configured for industrial production and containing either sulfadimethoxine (SDM) as a systemic marker or Rhodamine B as a topical marker was used. The overall proportion of dogs which took a bait and presented topical marker staining after door to door baiting was 59.1%. The total time and costs spent per bait accepting dog averaged 34 person minutes and US$4, respectively. Unconsummated baits were readily recovered. No unprotected human contacts with baits were recorded. Door to door baiting is a very specific but time-consuming method that enables a safe administration of vaccine baits to owned dogs. For transect line baiting, baits were distributed at a density of ca 3000 baits per km2 along double transect lines. Baits were recovered after 20 h. According to the proportion of SDM positive serum samples, 24.1% of owned dogs in the baiting area had consumed baits. Of all owned and ownerless dogs, presumably free-roaming during transect line baiting, > 40% had consumed baits. The total time and costs spent per bait accepting dog averaged 48 person minutes and ca US$20, respectively. The household census revealed 32 direct human contacts with the bait matrix which corresponds to 1.4% of inhabitants. Placing baits on transect lines gives the possibility to vaccinate dogs not accessible by vaccination systems which base on dog owner participation. However, the method is not specific, less safe than other systems, not easily accepted by the human population, and costly.
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[Emerging and re-emerging zoonoses. Local and worldwide threats]. MEDECINE TROPICALE : REVUE DU CORPS DE SANTE COLONIAL 1998; 57:7-9. [PMID: 9513171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Emerging or re-emerging zoonoses is a relatively complex topic. The concept covers not only new or recently identified zoonotic agents but also agents that are already known but appear in regions and/or species in which they have not been previously observed and agents that disappear then reappear in a country in the form of an epidemic outbreak. Many wild or domestic species and almost all infectious agents may be involved. In general intervention either by vaccination or by elimination of suspect or contaminated individuals is easier in domestic animals than in wild animals especially since the latter may belong to an endanger species. Because of the wide range of pathogenic agents, animal vectors and target populations, there are a wide variety of epidemiological patterns and adapted surveillance and control strategies must be used with various degrees of success.
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Abstract
The World Health Organization (WHO) estimates that human tuberculosis (TB) incidence and deaths for 1990 to 1999 will be 88 million and 30 million, respectively, with most cases in developing countries. Zoonotic TB (caused by Mycobacterium bovis) is present in animals in most developing countries where surveillance and control activities are often inadequate or unavailable; therefore, many epidemiologic and public health aspects of infection remain largely unknown. We review available information on zoonotic TB in developing countries, analyze risk factors that may play a role in the disease, review recent WHO activities, and recommend actions to assess the magnitude of the problem and control the disease in humans and animals.
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The role of veterinary public health in the prevention of zoonoses. ARCHIVES OF VIROLOGY. SUPPLEMENTUM 1997; 13:207-18. [PMID: 9413540 DOI: 10.1007/978-3-7091-6534-8_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Veterinary public health is a component of public health activities devoted to the application of professional veterinary skills, knowledge, and resources for the protection and improvement of public health. VPH activities involve a very diverse range of functions within public health which reflect the broad community of interests between veterinary and human medicine. Zoonoses continue to represent an important health hazard in most parts of the world, where they cause considerable expenditure and losses for the health and agricultural sectors. Although the situation is improving in the industrialized world, zoonoses prevention and control will remain an area of major concern in most developing countries. Recent observations in these countries show that expenses related to the prevention of zoonotic diseases in humans are likely to increase dramatically in the near future. Programmes for their control and eventual elimination in animal reservoirs are urgently needed. The technical knowledge exists to bring diseases such as brucellosis, rabies, and bovine tuberculosis under control during the first decade of the next century. To achieve this goal, constant efforts will be needed for the next 15 to 20 years. In addition, as trade in animal products and the movement of human populations continues to increase, the risk that zoonotic diseases will be introduced or reintroduced into certain areas is likewise increasing. Over the past five years, a number of zoonotic diseases have emerged as either new pathological entities or known agents appearing in new areas or as new strains. Through its coordinating and information gathering functions, the WHO Emerging Disease Surveillance and Control Division provides a source of both practical and technical guidance that can help solve these and other threats to human health posed by animals.
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CJD transmission. Nature 1997; 388:14-5. [PMID: 9214491 DOI: 10.1038/40255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Acceptance of candidate baits by domestic dogs for delivery of oral rabies vaccines. Onderstepoort J Vet Res 1997; 64:115-24. [PMID: 9352560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Protocols for evaluating oral rabies vaccine baits for domestic dogs were field tested in central Mexico, after which dog-food manufacturers and suppliers to the pet-food industry were advised as to potential ingredients for use in prototype dog baits. Bait-preference trials in which confined dogs were used were then undertaken, followed by field tests of free-ranging farmer-owned dogs in three towns in the Nile River Delta region of Egypt. Both confined and free-ranging dogs showed strong preferences for certain baits or bait coatings (poultry, beef tallow, cheese, egg and a proprietary product). Fish-meal polymer baits, widely used for wildlife species, were less preferred. In Egypt, a commercial dog-food-meal bait coated with beef tallow and dry cheese, was consumed at a rate approaching that of a chicken-head bait. The percentage baits that were actually eaten after they had been offered to dogs, ranged from 71-96% for household dogs tested in Mexico, 65-91% for confined dogs (beagles and mixed breeds) tested in the United States, and 32-88% for farmer-owned dogs tested in Egypt.
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Abstract
Many new human pathogens that have emerged or reemerged worldwide originated from animals or from products of animal origin. Many animal species as well as categories of agents have been involved in the emergence of diseases. Wild (e.g., bats, rodents) as well as draught animals (e.g., horses) and food animals (e.g., poultry, cattle) were implicated in the epidemiologic cycles of these diseases. Many of the agents responsible for new infections and diseases in humans were viruses (e.g., hantaviruses, lyssaviruses, and morbilliviruses), but bacteria, especially enteritic bacteria (e.g., Salmonellae and Escherichia coli) and parasites (e.g., Cryptosporidium) of animal origin, were also involved in major food and waterborne outbreaks. The public health relevance of some of these agents (e.g., new lyssaviruses and morbilliviruses) is not yet fully assessed. In addition the zoonotic nature of some other human diseases, such as Ebola and the new variant form of Creutzfeldt-Jakob disease, is suspected but not yet demonstrated. Finally, the possible future use of xenografts may lead, if precautions are not taken, to the emergence of new diseases called xenozoonoses.
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Abstract
This paper reflects on public health considerations on the voluntary release of anti-fertility vaccines for wildlife in the environment. The World Health Organization (WHO) has established a variety of recommendations on safety and efficacy requirements for the voluntary release of rabies vaccines used for oral immunization of animals. These requirements cover aspects of control of rabies and possible biological consequences in the target population. They also deal with the protection of the health of humans and other non-target species that might come into contact with the different oral rabies vaccines used in various parts of the world. These recommendations are laid down in several WHO publications. They are specific to the disease concerned, the target animal reservoir, the relationship and types of contact between humans and target animals, the vaccines and baits used and the respective conditions of oral immunization of wildlife in densely-populated areas. Many of these recommendations also apply to the development and application of contraceptive vaccines for wildlife carnivores. Additional safety requirements concern the transmissibility of the antigen, the reversibility of the intervention within an individual animal and in animal populations, as well as the species specificity of the antigen used. The management of animal populations that are reservoirs for zoonotic diseases is a possible means by which diseases that are transmissible from animals to humans could be prevented. Oral contraception by means of vaccines is an appealing method, provided that requirements for protecting public and animal health, as well as ensuring environmental safety, are precisely defined and strictly adhered to.
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Epidemiology of Mycobacterium bovis infection in animals and humans, with particular reference to Africa. REV SCI TECH OIE 1995; 14:733-46. [PMID: 8593405 DOI: 10.20506/rst.14.3.875] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The epidemiology of Mycobacterium bovis infection in animals and humans is described, together with a review of available reports on the distribution and prevalence of this mycobacteriosis in Africa. The significance of these reports is considered, with particular emphasis on the potential zoonotic importance of bovine tuberculosis as a cause for public health concern in Africa. Published data describing tuberculosis in Europe in the 1930s and 1940s show that bovine tuberculosis was considered to be a significant zoonosis: M. bovis was responsible for more than 50% of cervical lymphadenitis cases in children. Despite the paucity of information on M. bovis infection in Africa, there is sufficient evidence to suggest that it is widely distributed and is found at significantly high prevalence in some populations of animals. Some epidemiological conditions for the spread of M. bovis infection between animals and humans are very similar in Africa today to those in Europe in the 1930s, with the added and potent impact of the epidemic of human immunodeficiency virus infection. The public health threat of tuberculosis in Africa requires urgent investigation through collaborative veterinary/medical research programmes.
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Abstract
Chicken heads and two types of artificial bait were tested in Tunisia during two field trials in a waste disposal site carried out in 1988 and 1989 to compare their effectiveness as vehicles for the oral administration of antirabies vaccine to free-roaming dogs. Baits were made available for 36 hr and those that disappeared or were consumed were replaced on several occasions. In 1988, an artificial bait composed of fat and fishmeal (artificial bait type I) was tested. In the second trial, chicken heads and an artificial bait composed of polymerized fishmeal and wax (artificial bait type II) were compared. The vaccine containers were loaded with a topical marker (rhodamine B or methylene blue) to identify animals that had consumed baits. The artificial type I bait tested in 1988 was poorly accepted, but in the second trial, the number of chicken-head baits probably taken by dogs was more than seven times greater than the number of artificial type II baits taken. Thirteen dogs observed during the day showed topical marker staining. In both trials, most baits were taken during the night when dog activity in the waste disposal site was at its maximum. Artificial baits were characterized either by their lack of thermostability (type I, melting) or a certain attractiveness for cats (type II, fish flavor). Chicken heads fulfill established requirements for baits for vaccine delivery. They are well-accepted by free-roaming dogs, inexpensive, usually easily available at local markets, unattractive to humans, relatively easy to store in large quantities, and easy to handle.
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Zoonoses in the world: current and future trends. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1995; 125:875-8. [PMID: 7770747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Zoonoses still represent significant health problems in many developed and developing countries. Whereas rabies, brucellosis, and echinococcosis will remain the major zoonotic diseases to be tackled in developing countries for the next 20 years, it is very likely that many developed countries will have eliminated these diseases by then. As observed repeatedly in the past few years, new zoonoses are, however, expected to emerge in the near future. Due to ever-increasing animal and human movements these new agents, whether originating from the southern or northern hemisphere, will most probably spread throughout the globe very quickly. It is very probable, in view of the foreseeable changes in the developed (e.g. population aging) and developing world (e.g. population growth, urbanization) or both (e.g. AIDS pandemic, environmental changes), that this trend will continue and even intensify.
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[Current situation on human rabies control and anti-rabies vaccination]. SANTE (MONTROUGE, FRANCE) 1994; 4:203-4. [PMID: 7921688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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A dog ecology study in an urban and a semi-rural area of Zambia. Onderstepoort J Vet Res 1993; 60:437-43. [PMID: 7777333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Characteristics of dog populations and their accessibility for rabies vaccination were compared in an urban and a semi-rural area in Zambia. A total of 1,190 households were interviewed. In the urban study area (Mutendere, a low income suburb of Lusaka) only 11% of the households kept dogs with a dog:human ratio of 1:45. In the semi-rural area (Palabana) dogs were kept by 42% of households with a dog:human ratio of 1:6,7. In conjuction with the study of the dog populations in these two areas, immunization of dogs against rabies was provided by door-to-door visits in both study areas and also through central point vaccination in the urban area. The attitude of the public towards free rabies vaccinations was positive, although some misconceptions regarding indications and modalities of treatment following exposure to suspect dogs were found. Approximately 50% of the dog removals were as a result of disease and the demand for dogs was higher than the supply. Although only information on the owned segment of the dog population was obtained during the study, the proportion of ownerless dogs appeared to be very low. Generally, there is a need for better co-ordination between the different services involved in rabies control in Zambia to enhance the sustainability of vaccination programmes and improve the treatment of persons bitten by dogs.
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Economics of human and canine rabies elimination: guidelines for programme orientation. Bull World Health Organ 1990; 68:281-91. [PMID: 2118428 PMCID: PMC2393068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Analysis of the present situation in canine-rabies-infected countries shows that in most cases the levels of activities for controlling the disease in man and in dogs are far too low to prevent human deaths due to rabies and to eliminate the disease in the dog population. This article compares the two major orientations of a rabies control programme, i.e., prevention of the disease in man by intensifying and modernizing post-exposure treatment (strategy A) and canine rabies elimination by controlling the disease in the animal reservoir (strategy B). The operation of both strategies (A + B) together is also analysed. Based on the available data and assumptions for calculations of the costs, the results show that when the strategies are applied independently of each other, the annual cost of strategy B amounts to 25-56% of that of strategy A. When the two strategies are applied together, the actual annual spending related to the implementation of A + B becomes less than that of strategy A alone as from the fifth year following programme initiation. The sensitivity of the results was tested against selected fluctuations in the assumptions. An estimation of the costs of control activities per avoided death, according to the strategy applied, is also given. In countries where resources allocated to rabies control are inadequate in both the health and veterinary sectors, the comparison in costs and effectiveness of the two programme strategies for rabies elimination strongly suggests that consideration should be given to a national programme of dog rabies elimination. On the other hand, for obvious ethical reasons, if attention is paid to improvement of post-exposure treatment, then the national authorities should consider a planning horizon close to 15 years.
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